diff -r 000000000000 -r 6474c204b198 dom/workers/WorkerInlines.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/workers/WorkerInlines.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,24 @@
+/* -*- Mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 40 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+BEGIN_WORKERS_NAMESPACE
+
+inline
+void
+SetJSPrivateSafeish(JSObject* aObj, PrivatizableBase* aBase)
+{
+  JS_SetPrivate(aObj, aBase);
+}
+
+template <class Derived>
+inline
+Derived*
+GetJSPrivateSafeish(JSObject* aObj)
+{
+  return static_cast<Derived*>(
+    static_cast<PrivatizableBase*>(JS_GetPrivate(aObj)));
+}
+
+END_WORKERS_NAMESPACE